1
0
mirror of https://github.com/moparisthebest/pacman synced 2024-10-31 15:45:03 -04:00
pacman/lib/libalpm/conflict.h
Dan McGee bb3dada871 Convert package filelists to an array instead of linked list
This accomplishes quite a few things with one rather invasive change.

1. Iteration is much more performant, due to a reduction in pointer
   chasing and linear item access.
2. Data structures are smaller- we no longer have the overhead of the
   linked list as the file struts are now laid out consecutively in
   memory.
3. Memory allocation has been massively reworked. Before, we would
   allocate three different pieces of memory per file item- the list
   struct, the file struct, and the copied filename. What this resulted
   in was massive fragmentation of memory when loading filelists since
   the memory allocator had to leave holes all over the place. The new
   situation here now removes the need for any list item allocation;
   allocates the file structs in contiguous memory (and reallocs as
   necessary), leaving only the strings as individually allocated. Tests
   using valgrind (massif) show some pretty significant memory
   reductions on the worst case `pacman -Ql > /dev/null` (366387 files
   on my machine):

   Before:
     Peak heap:   54,416,024 B
	 Useful heap: 36,840,692 B
	 Extra heap:  17,575,332 B

   After:
     Peak heap:   38,004,352 B
	 Useful heap: 28,101,347 B
	 Extra heap:   9,903,005 B

Several small helper methods have been introduced, including a list to
array conversion helper as well as a filelist merge sort that works
directly on arrays.

Signed-off-by: Dan McGee <dan@archlinux.org>
2011-07-21 15:04:30 -05:00

42 lines
1.5 KiB
C

/*
* conflict.h
*
* Copyright (c) 2006-2011 Pacman Development Team <pacman-dev@archlinux.org>
* Copyright (c) 2002-2006 by Judd Vinet <jvinet@zeroflux.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef _ALPM_CONFLICT_H
#define _ALPM_CONFLICT_H
#include "alpm.h"
#include "db.h"
#include "package.h"
alpm_conflict_t *_alpm_conflict_dup(const alpm_conflict_t *conflict);
void _alpm_conflict_free(alpm_conflict_t *conflict);
alpm_list_t *_alpm_innerconflicts(alpm_handle_t *handle, alpm_list_t *packages);
alpm_list_t *_alpm_outerconflicts(alpm_db_t *db, alpm_list_t *packages);
alpm_list_t *_alpm_db_find_fileconflicts(alpm_handle_t *handle,
alpm_list_t *upgrade, alpm_list_t *remove);
void _alpm_fileconflict_free(alpm_fileconflict_t *conflict);
const alpm_file_t *_alpm_filelist_contains(alpm_filelist_t *filelist,
const char *name);
#endif /* _ALPM_CONFLICT_H */
/* vim: set ts=2 sw=2 noet: */